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| === Nicole Meyer | === Nicole Meyer-Vernet PSULib QB529.M485 2007 === . [[ https://observatoiredeparis.psl.eu/ | Observatoire de Paris ]] and [[ https://en.wikipedia.org/wiki/French_National_Centre_for_Scientific_Research | Centre National de la Rechereche Scientifique ]] [[ https://www.cnrs.fr/fr | website ]] .p009 Sun: mass 1.98892e30 kg, radius 695700 km, Luminosity 3.828e26 W +/-0.1% .p054 plasmas interact less with radiation than with plasmas .p057 [[ https://en.wikipedia.org/wiki/Fermi_energy | Fermi energy ]] . book's "comet-like" heliosphere model [[ https://www.science.org/doi/10.1126/science.1181079 | obsolete ]] . [[ https://www.science.org/doi/10.1126/science.1181079 | Imaging the Interaction of the Heliosphere with the Interstellar Medium from Saturn with Cassini ]] .p057 [[ https://pmc.ncbi.nlm.nih.gov/articles/PMC9726803/pdf/11214_2022_Article_939.pdf | heliospheric dust grains ]] .p057 plasma particle collisional free path increases strongly with speed, fast particles nearly collisionless .p064 Magnetic mirrors: particle moving towards converging/increasing field mirrors and reflects .p066 transverse gradient produces a small transverse drift .p069 [[ https://en.wikipedia.org/wiki/Vlasov_equation | Vlasov equation ]] [[ https://en.wikipedia.org/wiki/Liouville's_theorem_(Hamiltonian) | Liouville's theorem ]] .p080 "upstream kinetic energy converted to downstream [[ https://en.wikipedia.org/wiki/Enthalpy | enthalpy ]], high temperature .p083 viscous forces generally much less important than inertial effects, but . see E. M. Purcell [[ https://www.damtp.cam.ac.uk/user/tong/fluids/lowreynolds.pdf | Life at low Reynolds number ]] Am. J. Phys. 45, 3–11 (1977) .p083 ions transport momentum, determining viscosity; electrons transport heat, determining thermal conductivity .p084 Reynolds number very large for space plasmas, viscosity generally negligable .p084 1e6 K (kelvin) solar corona heat conductivity 1e4 W/m-K "same order of magnitude as brass" . [[ https://www.researchgate.net/profile/Anastasia_Vasileiou2/publication/263155220/figure/fig4/AS:550876301492239@1508350553460/Brass-CuZn33-properties-as-a-function-of-temperature-a-thermal-conductivity-b_W640.jpg | NO, brass approx. 150 W/m-K ]] Silver around 430 W/m-K .p084 conductivity low perpendicular to B, high parallel to B only if mean free path much smaller than scales of variation. .p088 [[ https://en.wikipedia.org/wiki/Magnetic_Reynolds_number | magnetic Reynolds number ]] convection ÷ diffusion .p090 magnetic field freezing [[ https://en.wikipedia.org/wiki/Alfv%C3%A9n%27s_theorem | Alfvén's theorem ]] .p090 plasmas in space tied to field lines, do not mix across field .p091 magnetized plasma has . inertia, corresponding to bulk kinetic energy ½ρV² . thermal pressure, corresponding to random kinetic energy ρkT/m . magnetic forces, corresponding to B²/2μ₀ .p092 V = B/(μ₀ρ)½ ≡ V,,A,, [[ https://en.wikipedia.org/wiki/Alfv%C3%A9n_wave#Alfv%C3%A9n_velocity | Alfvén speed ]] .p098 [[ https://en.wikipedia.org/wiki/Whistler_(radio) | Whistler ]] .p101 Bohr radius (hydrogen atom minimum energy 53e-12 meters, Bohr energy 13.6eV .p102 stripping atom (atomic number Z) of electrons requires approximately Z² × 13.6eV .p102 [[ https://en.wikipedia.org/wiki/Saha_ionization_equation | Saha ionization equation ]] .p105 cross sections for ionization and recombination .p106 AB⁺ + e⁻ → A + B coefficient of dissociative recombination β ~ 1e-11/√T (units?) .p107 Charge exchange A⁺ + B → A + B⁺, for hydrogen/proton cross section is 2e-19 meters .p110 solar wind density 5e6/m³ at 1AU, inverse square with distance . velocity 300 to 800 km/s, average 400 km/s, hence 2e12/m²s or 3.3e-15 kg/s . or 0.4 kg/s crossing area of earth disk .p113 sun 2e30 kg, ordinary star mass 0.1 to 100 Suns, smaller is a brown dwarf or giant planet .p122 minimum 8e55 protons, 7% of Sun .p123 rough estimate maximum 4e58 protons, 40 solar masses, accurate estimate about 80 solar masses .p124 graph of solar properties versus radius {{ attachment:SunDepth.png | | }} [[ | ]] [[ | ]] [[ | ]] [[ | ]] [[ | ]] [[ | ]] |
http://wiki.keithl.com/SolarWind
Basics of the Solar Wind
Nicole Meyer-Vernet PSULib QB529.M485 2007
Observatoire de Paris and Centre National de la Rechereche Scientifique website
- p009 Sun: mass 1.98892e30 kg, radius 695700 km, Luminosity 3.828e26 W +/-0.1%
- p054 plasmas interact less with radiation than with plasmas
p057 Fermi energy
book's "comet-like" heliosphere model obsolete
Imaging the Interaction of the Heliosphere with the Interstellar Medium from Saturn with Cassini
- p057 plasma particle collisional free path increases strongly with speed, fast particles nearly collisionless
- p064 Magnetic mirrors: particle moving towards converging/increasing field mirrors and reflects
- p066 transverse gradient produces a small transverse drift
p080 "upstream kinetic energy converted to downstream enthalpy, high temperature
- p083 viscous forces generally much less important than inertial effects, but
see E. M. Purcell Life at low Reynolds number Am. J. Phys. 45, 3–11 (1977)
- p083 ions transport momentum, determining viscosity; electrons transport heat, determining thermal conductivity
- p084 Reynolds number very large for space plasmas, viscosity generally negligable
- p084 1e6 K (kelvin) solar corona heat conductivity 1e4 W/m-K "same order of magnitude as brass"
NO, brass approx. 150 W/m-K Silver around 430 W/m-K
- p084 conductivity low perpendicular to B, high parallel to B only if mean free path much smaller than scales of variation.
p088 magnetic Reynolds number convection ÷ diffusion
p090 magnetic field freezing Alfvén's theorem
- p090 plasmas in space tied to field lines, do not mix across field
- p091 magnetized plasma has
- inertia, corresponding to bulk kinetic energy ½ρV²
- thermal pressure, corresponding to random kinetic energy ρkT/m
- magnetic forces, corresponding to B²/2μ₀
p092 V = B/(μ₀ρ)½ ≡ VA Alfvén speed
p098 Whistler
- p101 Bohr radius (hydrogen atom minimum energy 53e-12 meters, Bohr energy 13.6eV
- p102 stripping atom (atomic number Z) of electrons requires approximately Z² × 13.6eV
- p105 cross sections for ionization and recombination
- p106 AB⁺ + e⁻ → A + B coefficient of dissociative recombination β ~ 1e-11/√T (units?)
- p107 Charge exchange A⁺ + B → A + B⁺, for hydrogen/proton cross section is 2e-19 meters
- p110 solar wind density 5e6/m³ at 1AU, inverse square with distance
- velocity 300 to 800 km/s, average 400 km/s, hence 2e12/m²s or 3.3e-15 kg/s
- or 0.4 kg/s crossing area of earth disk
- p113 sun 2e30 kg, ordinary star mass 0.1 to 100 Suns, smaller is a brown dwarf or giant planet
- p122 minimum 8e55 protons, 7% of Sun
- p123 rough estimate maximum 4e58 protons, 40 solar masses, accurate estimate about 80 solar masses
- p124 graph of solar properties versus radius
